// yield/thread/win32/semaphore.cpp

// Copyright (c) 2011 Minor Gordon
// All rights reserved

// This source file is part of the Yield project.

// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
// * Neither the name of the Yield project nor the
// names of its contributors may be used to endorse or promote products
// derived from this software without specific prior written permission.

// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL Minor Gordon BE LIABLE FOR ANY DIRECT,
// INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
// THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#include "yield/exception.hpp"
#include "yield/time.hpp"
#include "yield/thread/semaphore.hpp"

#include <Windows.h>

namespace yield {
namespace thread {
Semaphore::Semaphore() {
  hSemaphore = CreateSemaphore(NULL, 0, LONG_MAX, NULL);
  if (hSemaphore == NULL)
    throw Exception();
}

Semaphore::~Semaphore() {
  CloseHandle(hSemaphore);
}

void Semaphore::post() {
  ReleaseSemaphore(hSemaphore, 1, NULL);
}

bool Semaphore::timedwait(const Time& timeout) {
  DWORD timeout_ms = static_cast<DWORD>(timeout.ms());
  DWORD dwRet = WaitForSingleObjectEx(hSemaphore, timeout_ms, TRUE);
  return dwRet == WAIT_OBJECT_0 || dwRet == WAIT_ABANDONED;
}

bool Semaphore::trywait() {
  DWORD dwRet = WaitForSingleObjectEx(hSemaphore, 0, TRUE);
  return dwRet == WAIT_OBJECT_0 || dwRet == WAIT_ABANDONED;
}

bool Semaphore::wait() {
  DWORD dwRet = WaitForSingleObjectEx(hSemaphore, INFINITE, TRUE);
  return dwRet == WAIT_OBJECT_0 || dwRet == WAIT_ABANDONED;
}
}
}
